Buyers and sellers gather in a sweltering, previously abandoned building in the Greek city of Volos, some 200 miles north of Athens. There's a bit of everything available here – books, eggs, clothes, kids' toys, and even an old fax machine.

Player utilities

But there isn't a euro in sight. On the eve of a vote which may determine whether Greece stays in the euro zone, these Greeks have moved beyond the euro, at least here. This market is the brainchild of a network of people who have chucked the euro in favor of the TEM – the Greek shorthand for "Alternative Local Currency."

"In the network, people can trade their goods and services. They don't need money for that. They just need time and the desire to do it," said Christos Papaioannou, one of the network's founders. It's kind of like bartering on steroids, he added.

"We can see it as exchanging favors, if I do a service for you, then you owe me a favour, and I can use that favour to get some service from someone else. So, we don't have to exchange directly, I can get it from some third person."

Let's say someone offers a haircut. The network determines that's worth 10 credits. (To make it easier to set prices, one TEM is valued at one euro.) The haircutter can then spend those credits on products at the market, or on services offered by someone else.

To be clear, there is no real "currency" that changes hands – no scrip. Instead, credits are tracked, goods and services are listed, offered and accepted, through an open-source computer program designed for this kind of "community banking."

The original idea for the network predates the economic crisis, said Papaioannou, adding it's about coming up with different ways for people to interact economically, so "that people do things together, and take things in their own hands, basically."

It's an idea that appeals to Euripides Siouras, who joined the TEM network in December 2010. "I thought that the existing economic system was something like a war. It wasn't made for the citizens," Siouras said.

And what services does he offer? "Massages, back remedies, and general alternative therapies," Hueras said – things that more and more Greeks could probably use these days, especially in Volos.

The city has been hit hard by the crisis, said Volos Mayor Panos Skotiniotis. When construction fell off, the region's cement and metal industries suffered. Unemployment is rising, and local funding from the Greek state is down 40 percent over the past three years.

Skotiniotis said the municipality can't support the TEM network in any official way. But he certainly sees its value. "It goes without saying that this currency is not substituting for the official state currency, the euro," said the mayor. "But it's a supplement for people who can't meet their own needs."

Back at the market, I'm told the TEM network in Volos is growing quickly. More than 1,000 people have joined or are waiting to join in this city of 150,000. Katarina, who joined a month and half ago, is selling homemade liqueurs, jams and sweets. For her, the network isn't just about creating an alternative social structure. It's about survival.

She uses her credits to buy staples – vegetables, fruits and eggs – from others in the network. She said she wishes the TEM network were bigger – she wants to be able to buy things like olive oil and meat. Katarina said she's been unemployed for five months now. When I asked if she's received any help from the local government, she laughed. "The state is completely absent. All of our politicians are cheats. They robbed us." Then she added: "You go tell Obama that."

Nearby, 18-year-old Olina is helping her mother sell some of the family's clothes. "I don't think that clothes matter now, at this moment, with all the crisis. I think food is more important," Olina said.

She said she's studying communication and would like to write for a fashion magazine like Vogue someday. For now, being in the TEM network has helped her family put food on the table.

Like almost all of the people I spoke to in Volos, Olina said she doesn't expect Sunday's elections to change much, no matter who wins. Little wonder then that Volos' alternative currency idea, or something like it, is now catching on in 7 or 8 other cities and towns in Greece.

The only question, it seems, is if the TEM will be an alternative for the euro – or the drachma.